Grate for boiler-furnaces



(No Model.)

W. BOWERS.

GRATE FOR BOILER FURNACES. No. 263,470.

Patented Aug. 29, 1882. J H O Jrwemor:

tl'nirnn STATES PATENT @nricn.

WILLIAM BOWVERS, OF OARBONDALE, PENNSYLVANIA.

GRATE FOR BOILER-FURNACES.

SPECIFICATION forming part of Letters Patent No. 263,470, dated August29,1852.

Application filed July 22, 1882. (No model.)

and useful Improvement in Grates for Boiler- Fnrnaees; and I do herebydeclare that the following is a full, clear, and exact description ofthe same.

My invention relates to improvements in moving grates forboiler-furnaces; and it consists partly in the improved means foroscillating the bars composing the grate; further, in an improvedframing or hearing bar in which the sections are journaled further, inthe means forprotecting and securing the gearing; and, finally, in thegeneral improvements in details of construction, all of which will bemore fully hereinafter described and claimed.

My invention is an improvement upon that forming the subject of acertain application for Letters Patent filed by me June 22,1882. In thatapplication I showed a series of interlockin g bars each havingoppositely-set quadrantshaped teeth, such bars being journaled in apeculiar side piece of the frame and oscillated simultaneously byhangers and a compound lever. In my present invention I use the sameshape of bar, in connection with improved moving devices.

In the accompanying drawings, Figure 1 is a plan view of a furnace-gratecomposed of two beds or sections. Fig. 2 is a side elevation, the outerside of one of the bearing-bars being removed. Fig. 3 is a modification.

It should be premised that the grates for boiler-furnaces are of largesize, while the individual oscillating bars are composed of teeth notover eight inches in length. It being impracticable on a drawing toindicate the relative proportions of the frame and bars, I have shownonly four of such bars in each section or division of the grate.Ordinarily the grate would be composed of a number of such sections. Ihave here, however, shown two only.

Each section is composed of end bars, A A,

with which are cast the stationary quadrant shaped teeth B, Fig. 1.

O 0 represent the peculiar open side or bearin g bars. These bars may becast of one piece, if desired, and have a longitudinal slot extendingthroughout their whole length, as shown. On each side of this slot arecorresponding grooves or bearings for the spindles or journalsof thegrate-bars belonging to opposite sections, and at a point between thesebearings are braces 1, Fig. 1.

The grate-bars F F are constructed as in my application referred to.They consist of a central rib and a series of semicircular projections,each forming two oppositely-projecting quadrant'teeth. Each barisofaflat narrow lozenge shape on top and tapers to a comparatively sharpcurved edge below, so that air is freely admitted and clinkers and ashesare prevented from obstructing the openings. These bars are providedwith trunnions G, which bear in the grooves in the side bar, each sidebar supporting the end of grate-bars belongingto adjacent sections.Ordinarily I prefer to oscillate only every alternate bar of a sectionin shaking the grate, and this'is accomplished in the following manner:The end ofthe trunnion of each bar is squared, and on this squared endis slipped a segmental gear, H, which is thus inclosed within the slotin the side bar. It is unnecessary to key the gearing on the squaredend, since it is prevented from slipping off by the wall of the slot inthe side bar. The segments are of the same shape as the grate-barsthemselves, and when oscillated perform the functions of a grate-bar,since the fuel lies upon them and will be agitated by their upward anddownward movement. The gears H are placed alternately on opposite endsof the bars, as shown in Fig. 1.

Since the gears form part of the grate and are intended to be oscillatedinconcert with the bars, and since all the bars are intended to be movedin the same direction, as explained in my former application, meansmustbe provided for giving this simultaneous oscillation in the samedirection to the segments and'bars. This is accomplished by means of thetoothed racks I, which slide in the bottom of the slots in the sidebars. Friction-rollers K K are journaled in the walls of the slot, andupon such rollers rests the rack, the teeth meshing with the seg ments.To the end of the rack is attached the operating device, preferably bymeans of a link, L, pivoted to a lever, M, which is in turn pivoted to astandard, N, secured to the frame. The movement of the lever backwardand forward produces a direct reciprocating motion of the rack, and assuch rack meshes with seg too ments on alternate grate-bars (of each section) it follows that every other grate-bar will be oscillated in thesame direction. Sufiicient movement is permitted the gearing to allowthe bars to be turned a full quarter-rotationforthepurposeot'dumpingthet'uel. Ofcourse the levers at opposite sidesof the same sec tion may be operated together, in which case all thebars might be operated at once in the same or in opposite directions.

In the modification shown in Fig. 3 the segments are placed upon thesame end of all the bars in a section, while the rack engages with themall. Hence only a single rack is necessary to oscillate all the bars ina single section.

The advantages of the slotted side or bearing bar will be readilyapparent. It permits the air to have access to the tire, while at thesame time it is broad enough to att'ord bearing-surface for the bars ofsepa ate sections of the grate. It forms a protection to the gearing andprevents the segments from working ott the trunnions, while it is anexceedingly light and yet strong support for the parts.

If pret'erred, the segments maybe cast with the bars; but I prefer tomake them removable, since it warped or otherwise injured by heat thebar may be lifted out and the gearing replaced by a new one. I mayalsoprefer to make each tooth of the grate-bar removable from itscentral rib for the same purpose.

The racks are provided also with stops 1) 2, which prevent them frombeing moved too far in either direction.

Having described my invention, I claim-- 1. In a grate, the combinationof the pivoted interlocking bars, segmental gears, and a sliding rack.

2. The combination of the slotted side or hearing bars, the interlockinggrate-barsjournaled therein, segments attached to said gratebars, and arack engaging with said segments.

3. In a grate composed of two or more sec tions, the combination, withthe interlocking teeth, ot'the slotted bearing-bars adapted to separatethe sections, the sliding racks, and the segments placed on oppositeends of alternate bars.

at. Inagrate,thecombinationot two or more sections composed of pivotedinterlocking bars, with segments connected to such bars and adapted tohe moved in concert therewith, whereby such segments operate asgrate-bars, as described.

5. A side or bearing bar for a grate having a central slot, incombination with the segments inclosed thereby and the rack.

6. In agrate, the combination of the pivoted bars, the segments, therack and its operatii'lg-lever, and the rollersjournaled in the slottedside bar.

In testimony whercofI have signed my name to this specification in thepresence of two subscribing witnesses.

WILLIAM HOWE 1S.

Witnesses:

I. E. Bowans, WM. G. Sownns.

